


A Wolf's Cry

by BathianKittlore



Category: Undertale (Video Game)
Genre: I just want to write a silly story, Multi, POV First Person, Rated mature for various things, Reader Is Not Frisk, Transformation, tagging things is hard
Language: English
Status: In-Progress
Published: 2016-07-29
Updated: 2016-08-03
Packaged: 2018-07-27 11:46:38
Rating: Mature
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 3
Words: 4,155
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/7616851
Author URL: https://archiveofourown.org/users/BathianKittlore/pseuds/BathianKittlore
Summary: <blockquote class="userstuff">
              <p>For years, I thought I was a monster. A creature that shouldn't exist, shouldn't even be alive. That's when I met them.</p><p>That's when I met him.</p>
            </blockquote>





	1. The Day The Barrier Shattered

**Author's Note:**

> Welcome to my second story on the website! My first story, Only The Fearless, was me trying to do something different and unique. A love story between a human and everyone's favorite Goat Mom. This story is a little bit more... comfortable I guess?
> 
> Sans seems to be everyone's favorite subject for romance, so I'm giving it a shot here, but with a twist. No silly human mate here. Nope. Just a very confused shape-shifter... Oh well you'll see what I mean. Keep reading!

The day had started out well enough for me. The birds were singing. The flowers were blooming. It was perfect weather for a game of catch. Wait, no. No it wasn't. It wasn't good enough for a game of catch. I didn't mean it like that, I really-

_Come on, you know I'm a wolf and not a dog, right?_

Ugh, there she goes again, reminding me once again what I was and what I wasn't. I grumbled a little, grabbing a foil-wrapped package of blueberry pop-tarts from the pantry before filling my travel thermos with as much hot chocolate as I could manage to cram into it.

Oh, wait, you probably are wondering who the heck I am, aren't you? Well, my name is River, and my 'wolf' friend is Midnight. From what I could tell, she had a proper name at one point, but she can't seem to remember it. She says she 'fell down' after some sort of war between humans and monsters, but I'm not sure if I can believe that or not.

I guess I should explain where the heck this all started.

Seventy years ago, I was casually wandering through a nearby forest, lost in thought. My parents had decided that it was time for me to marry, and had started sending suitor after suitor my way. I was growing frustrated with them. I didn't want to marry some snot-nosed brat from some rich family! I wanted to live my own damn life, meet the man (or woman) of my dreams, and be happy forevermore.

That's when I stumbled across a massive grove, complete with a small lake that seemed to shimmer with a soft neon blue glow. I was mesmerized by it from the very beginning, slowly kneeling down next to the water. The stars had already come out, and the moon was slowly rising above the treeline, making the water shine even brighter than before. 

I wasn't thinking straight. I was just so... lost. Confused. Angry.

I wanted control of my own life.

I cupped my hands and dipped them into the water, carefully bringing it up to my lips. I wasn't sure what I was expecting. Maybe there was some sort of poison in the lake that would end my life. Maybe it would be too salty, like sea water, and I'd die to dehydration. Maybe I had just discovered the most pure water in the region and would make so much money I could finally leave this terrible life and begin my own adventures.

I wasn't expecting a voice to enter my head. I wasn't expecting the sudden rush of something caressing the back of my head. New thoughts, new feelings. A new being, latching onto me in desperation. The voice was weak, pleading.

I let them in.

I never returned home.

* * *

Work was always a pain, especially this time of the month. Midnight always grew restless after a few weeks of being cramped up in my own head, unable to stretch her own legs, run free in the forests around Mount Ebbot. I just grit my teeth and focused on the task at hand.

_Sorry, River. You just promised me that we'd go for a run last week, and we didn't go. Honestly, you should take MORE trips to the mountain. The more you hold off from changing, the more it hurts in the long run._

"Ugh, I hate it when you're right, Midnight. I just... you know I don't like those first few seconds. It's embarrassing!" I said in a quiet whisper, thankful that I had a private office. Working from home had always been a more preferable choice, especially with my newly acquired immortality thanks to the 'monster' who lived in my Soul, but these past few years, I had to resort to this job at the local university. I helped with a lot of different things; tutoring the poor students who didn't quite get as much help as they required, graded tests, fetched coffee for the various professors on campus. You know, pretty much all the hard work.

Today was a rather slow day, due to the semester being over. As such, all I did was stare at my reflection in the computer screen, grumbling to myself.

Ever since the first change, my eyes had shifted from a dull doe brown to a brilliant emerald green, flecked with tiny pieces of amber. My hair for the last few years had been dyed a deep red and kept in a nice, easy to manage bob. As time wore on, I would dull out my colors, trying to emulate aging as best I could. This included using makeup to the best of my abilities. Small imperfections, things that would normally appear after a while, but never would for me, thanks to Midnight.

I sighed, shaking my head as I pushed away from the desk. The day wasn't going anywhere, might as well clock out early. The least I could do was get to the Lake early to give Midnight a few more hours with my body.

A soft, contented hum filled my head. It seemed Midnight was pleased with this choice. I smiled wide.

"Knew you'd like that plan. Would you like me to play your playlist on the drive up?"

_Oh, of course River. You know I prefer the sound of a piano over whatever... sounds you seem to enjoy._

"Oh come on, Midnight!" I laugh, shaking my head as I stepped into the parking lot, fishing my keys out from my jacket pocket. "I just KNOW you'll start to appreciate the wonderfulnesses that is rock and roll some day! But fine, we'll listen to some Ray Charles today."

_You humans are so weird. So very different, yet so the SAME. It's amusing to say the least._

"What'ya mean by that?" I ask, honestly a little shocked by her statement.

_Monsters are varied in appearance, but all are made of love and compassion. And magic, of course. Humans, on the other hand, are physical beings with a wide range of emotions, yet you all have similar structures. It just... amuses me how your kind seem to always find reasons to fight each other, even when you're all the same._

I sigh a little, slipping into the car and firing it up. The drive was going to be a long one, as always. "I guess. Granted, neither of us exactly fit the bill of being a monster or a human anymore, right? We're like... both now? Is that how this whole thing works?"

_Yes dear. We're both. And we're neither._

Real cryptic, Midnight. Really fucking cr-

I barely maintained control of the car when the earth started to shake. The fuck was that? Since when did we get earthquakes in Ebbot?

"Shit shit shit fuck shit fuck," I muttered to myself, finally pulling over to the side as the quake settled down. I rested my forehead against the steering wheel, trying to calm my hyperactive heart.

_That... was strange. I haven't felt anything like that since before the war ended. There was a lot of magic involved in that explosion. Maybe... maybe we should hurry to the Lake. I want to go investigate, and we're going to have to do it in my form._

"Fine. Just give me a moment. I almost flipped the car just now, Midnight."

This was going to be a rather interesting evening. That's for damn sure.

* * *

i couldn't believe it. we were here, on the surface. the kid finally pulled through after countless attempts. i couldn't help but shake my head as we all gazed out at the setting sun. i barely paid attention to the rest of the group, only piping in when paps decided to ask about the 'ball' on the horizon.

things were gonna be better now. the kid was gonna stay with tori, monsters were gonna start buildin' a small village on the mountain, get settled in before we approach the humans to get acclimated back into society once more. i chuckled a little, pulling my gloved hand out of my jacket pocket, feeling the warmth of the setting sun on my bones for the first time ever. everyone seemed eager to explore a bit, and i was inclined to agree.

time to find a place to set up camp for the night. i can't wait to look up at the stars and the moon. this was so much better than the wishing room in waterfall.

maybe it was a good thing i hadn't given up all those resets ago. 

 

 

 


	2. Caught With My Pants Down

**Summary for the Chapter:**

> Midnight and River make it to their special Lake in the middle of the forest, preparing to investigate the massive burst of magical energy that caused them to almost crash.
> 
> Someone catches them in the act of Changing...

**Notes for the Chapter:**

> And now, the first transformation of the story! Wooo
> 
> Thank you so much for reading this. The updates are probably not going to be as fast in this story as my other story, but I do want to put up things when I get the chance.
> 
> Enjoy the show, Sans!

The rest of the drive up to the mountain was rather uneventful for me. I mean, other than Midnight practically bouncing off the 'walls' inside of my own head in excitement. She was really eager to investigate the whole 'magic' thing that just happened.

"You do realize it could have just been an earthquake right?" I say, trying to stop the wolf's excitement from becoming headache inducing.

_Are you kidding me? This is probably the best thing that could have happened! If that was the Barrier shattering, then Monsters are free from the mountain! You won't have to hide your true self anymore!_

I scoff at this. "What? Hide? What are you talking about?"

_You know exactly what I'm talking about. You like to thing that your human self is the real you, but deep down in your very Soul you know that's not the case. You're human, but you're also a Monster. And you know being in your wolf body is more comfortable than wearing your human skin._

I sigh, slamming my car door shut in the small rest stop parking lot, carefully moving down one of the well used footpaths before turning suddenly to the right, eyes focused on the much more worn out path I had carved out in the decades of making this journey. I hated it when my companion spoke the truth. It WAS easier, more comfortable to simply stay in that form, but it wouldn't work. I'd be hunted down and killed, or captured and experimented on by the government in an attempt to weaponize me. It wasn't fair, damn it! Before I could get too angry at myself, I pushed through the last set of bushes, standing in the Grove from so long ago. The moment I saw the pristine lake, I let out a content sigh. No matter how angry I was about certain events, this place had a way of calming me down in an instant.

"We're here, Midnight. Ready for the Change?"

_Of course I'm ready, dear. Don't forget to fold your clothes._

I roll my eyes as I carefully moved to a tree near the northern edge of the Grove, my shirt up and over my head before I stopped next to the tree I always used to store my clothes. There was a small hole near the roots of the tree, a perfect place to stash things away, that Midnight and I had dug up about four years into my new life. I sighed at the memory before quickly folding the shirt and setting it down on the grass. Next came my bra, thankful for the privacy of the moment. I wasn't exactly self-conscious of my own figure, but the human part of me still freaked out over the prospect of being seen naked.

Next came the footwear and the pants, enjoying the sensation of grass under my feet, giggling when a few stray blades of it brushed between my toes. Finally, the matching panties to my bra, folded with the utmost care and stashed between the folds of the pants. There was no way those were getting ruined. I loved those panties. They were so silky smooth...

Just like my fur as a wolf.

I grumbled to myself, taking a seat with my bare back against the tree, closing my eyes. "Alright Midnight, go ahead. Take control and all that nonsense. I'll b _e watching oh COME ON why don't you ever let me finish talking!_ "

My eyes opened, the amber flecks slowly spreading across my eyes like a wildfire as Midnight gained control of the body to use her magic for the Change. "Oh please, you love it when I take control, dear." I flipped a mental middle finger, prompting a giggle as my hand slowly lifted up, the amber glow covering the fingers. The Change, for what it's worth, never really hurt. It just felt weird, feeling my physical form seeming to grow more transparent as the matter is converted into magic. It wasn't unpleasant in the slightest, watching my hand grow crystal clear before reshaping into something, a mixture between a hand and a paw, nails tipped with black claws, the fingers themselves longer, more dexterous. Fur slowly creeping up my arm, as well as the rest of my altering body. Some of the weirdest changes for me were my feet and legs. The heels stretching up to form an extra joint, similar to a canine's rear legs. It added a few extra inches of height to my form, which was always a plus. I loved being taller like this.

The weirdest change of all, however, was my face. I always had to close my eyes during it, the feeling of my jaw and nose pushing outward, my ears pulling upward, my hair growing into a much longer mane to match River's hairstyle from when she was alive. All of these things, all of these changes... only took about a minute to occur. I always thought the changes had been longer, but after setting up a timer one day many years ago, Midnight had proven to me that she worked really fast.

Then the headache started. I clutched at my head as Midnight released her hold on the body, retreating back to recover her magic. That's what would  hurt in the past. Not the change itself, but the aftermath. It took a lot of magical energy to do this sort of thing, and with me not really willing to come out here more often than once every few weeks, it meant that she didn't have as much magical stamina as she should have.

One day, possibly when I have to 'reset' myself after this current 'life' was over, I was going to let her have more time shifting back and forth. Just to let her have some fun.

_You really don't need to do that, River. I know you would rather stay human all the time._

"Psh, get real, Midnight. Just wish the 'crash' wasn't so severe, you know? Would much rather not have to sit here for five minutes trying to recover." I leaned my head back against the tree trunk, closing my eyes, listening to the forest around me. My left ear twitched slightly at the sound of a breaking twig, instantly turning in that direction.

I nearly screamed at the sight in front of me.

Someone was staring at me from the bushes nearby. Someone had possibly seen me change.

That someone looked like a skeleton...

* * *

the stroll down the mountainside was rather peaceful. the birds were singing, the flowers were blooming. everyone was having a good time exploring. after undyne and alphys caught up to pap to make him slow down, we all kinda went in different directions to explore the forests. tori and asgore wanted to see if there were any landmarks they recognized from their time on the surface, and frisk wanted to spend time with the former royal couple. i couldn't help but chuckle at the kid's determination to see them kiss and make up, even if it took a very long time.

i stumbled across a massive grove, complete with small lake. was pretty neat, especially with the slightly glowing water... wait. what?

i took a quick shortcut right to the edge of the water, kneeling down beside it. i could practically feel the magic humming from it. a combination of the mushrooms from waterfall and the dust of a fallen monster. that amount of magic could really do something if anyone ever found this lake. well, probably not to us monsters, but to a human? who knows what would happen.

the sound of someone talking woke me out of my own thoughts. the fuck? who is out in the middle of the woods other than the seven of us who just left the underground? quickly, i shortcut to the north end of the lake, behind several trees to catch a glimpse at whoever was nearby. i wasn't really expecting a naked woman sitting against a tree.

i wasn't expecting to see her slowly change into a monster.

my soul hummed roughly in my own chest as i watched the display. the woman clearly wasn't in a panic, which means she had been doing this for quite some time. she had such control of her own changes, keeping them steady. before he knew it, she was finished, a full blown wolf monster. black fur, green and amber eyes. something very befitting of snowdin, for sure. but she clearly wasn't from the underground. her magic was the same as from the lake. the human had consumed the water for some reason... reawakening a dead monster in her own body.

i took a step forward, wanting to get an even closer look, my curiosity reaching it's peak.

i didn't really think this through, because my damn slipper stepped on a branch. her head snapped up in an instant, catching me in a shocked gaze. she could have easily screamed, but she bit it back by wrapping both of her hands around her muzzle, her eyes wide in terror.

guess being a skeleton would do that to someone... 

**Notes for the Chapter:**

> There you have it! Lemme know what you think of the story so far. Wanted to try something different with the change, seeing as... well, monster's are made of magic, not physical matter. Was a little weird, but I liked the concept in my head and just went with it.
> 
> See you all in chapter three eventually!


	3. An Awkward Attempt At Flirting

**Summary for the Chapter:**

> River and Sans have a chat about monsters and the Lake who granted her this special gift. Midnight wants to jump his bones. Hilarity ensues.

**Notes for the Chapter:**

> Thank you all for givin' this story a chance, by the way. It's probably not THAT great but I wanted to try something a little different than what I was doing with Only The Fearless, so here we are!

There was a walking, breathing skeleton not twenty yards away from me, watching me with a curious expression on their skull. The bones were malleable, moving like a proper face as they examined my altered form. Midnight was silent the entire time as I lay there, barely able to move my legs still during the 'Crash' portion of my changes. The magic of my modified Soul was still weak, and with this new body, that meant not running away from Mister Grim Reaper and his blue jacket. And his basketball shorts.

And his pink slippers? The hell?

Quickly I move my arms to cover my naked form, cheeks flushed with embarrassment. "Wh-who are you?" I ask. "How long have you been w-watching me?"

The skeleton sighed, taking a couple steps forward, holding up his left hand to try and defuse the situation. "heh, well normally i'd offer to shake your hand first, but i guess i gotta make the breast of the situation and just tell ya my name. it's sans. sans the skeleton."

I couldn't help but roll my eyes back at the pun, closing my eyes for a moment. "My name is River. If you were hear the entire time, the other... me... is Midnight. This is technically her body. I'm a human, but she was a monster. Something about 'falling down' near the Lake here. She never expressly said what that means, but I have a gut feeling about it. So... you're actually on the surface now?"

"yup. we just broke the barrier. the rest of our group is explorin' the forest right now. want me to leaf ya be, or ya wanna meet the king and stuff?"

That was an offer I couldn't refuse. Maybe meeting these other monsters will help Midnight.

"Sure! Just... uh... well I can't exactly move yet. The Change takes a good deal of magic, and being both a human and a monster, I don't exactly have a skele-ton of it. Can't feel my legs just yet. Oh yeah, don't drink the water... that's what made me like this."

I could actually see the bone-brow raise up in surprise, the perma-smile of the skeleton faltering. "you seriously drank from that thing? why? that lake is saturated with magic from the underground, and it's infused with the essence of a fallen monster to boot. what drove you to drink from it, buddy?"

I grumble at the question, slowly rubbing my eyes. "Alright, I'll tell you about it.

It started about seventy years ago..."

* * *

the kid sure could weave a story together, i can give them that. seventy years is a long time to be hidin' your true self from the rest of the world. as she spoke, i took a quick peak at her soul, and couldn't help but smile. it was the brightest shade of jade i had ever seen, even brighter due to the outer edges and the very core of it being a monster's white. no wonder she needed breaks between moments in her story, she was bone-dry on magic at the moment. not having any sort of monster food to help sustain that magic could have killed her, if she hadn't been able to change back and forth at will.

when story time was over, i rose to my feet, reaching out a hand (sans the whoopee cushion) to help the girl up to her feet. "here ya go, kiddo. let's go find the others. gotta make sure frisk doesn't drink from the lake water. or even touch it. with a fifty foot pole."

river couldn't help but roll her eyes at me, poking me carefully in the ribs with a clawed finger. "You sound like an overly-cautious grandpa. The water itself is harmless, things only started happening when I ingested the water itself. But you're probably right... thankfully the rest of the Grove should be large enough to camp out here." the woman stopped for a moment, her eyes unfocused for a moment, muttering something to herself. "No, Midnight, I'm not going to ask him that. No... no, we will do what we do every time that comes up. I don't care if he's hot, Midnight, we -just met him- okay? There's no way he'd want to-"

"uh, river? what's goin' on?"

the woman couldn't prevent herself from blushing when she realized i was still standing there, watching. the color of her blush was rather interesting. a combination of jade and amber, her soul and her eyes. i couldn't help but wonder just how many times i could make her blush. make her smile. that'd be a nice way to spend my time on the surface.

"Oh, sorry. Little Miss Wolf up in my head clearly wants a trip to the bone zone, and I'm having to quietly remind her that you're not exactly a toy. That you're a person with thoughts and feelings and a Soul. Someone who can do so much better than a fucked up human/monster hybrid bitch."

my eyes grew wide at that, carefully stepping towards the wolf woman, instantly regretting it. river... or rather, whoever the monster that lived inside of river, was entering her heat cycle. no wonder the kid was up here on the mountain. probably needed to get away from humans before she changed unwillingly. enough movies had fallen down for me to know my monster tropes, and a werewolf was one of the classics on the surface.

"tibia honest, i don't think there's anyone more 'fucked up' than me. and..." i smile wide, letting my teeth part and my tongue slip out, winking casually at the now confused wolf hybrid. "i think you're rather cute."

* * *

_Oh fuck he has a tongue oh fuck yes let me touch him let me touch him L E T M E T O U C H H I M._

I shiver, heat coursing through my veins as the skeleton pulled his magical tongue back into place, his permanent smile back in place. I swallowed hard, carefully testing my legs before bolting towards the lake, dunking my entire head into the water to try and cool myself off. I even made sure to curl my tail down between my legs to cover myself as I did so, my cheeks flushed. Once I was finished soaking myself, I turned towards where the skeleton had been standing, only to nearly fall backwards into the water.

Somehow he had followed me without making a single noise, a massive shit-eating grin plastered on his skull.

"heh, no need to go falling for me, pup. i know midnight is probably goin' crazy with need, but should probably introduce you to the others first, ya know?"

I nod in agreement to this, carefully shaking my head to clear off any remaining water droplets before falling in behind him.

We didn't go two steps before a taller skeleton came crashing into the Grove, alongside several other monsters of various appearances. Sans gave a low chuckle, shaking his head as he approaches the rest of the group. I followed close behind, shaking like a twig.

Let's just pray this goes better than my introduction to Sans. 

 

**Notes for the Chapter:**

> Not yet, filthy sinners. You have to waiting a bit before the true fun can begin.

**Author's Note:**

> Well here we go. Next chapter we experience River's first change, as well as meet the rest of the cast! Lemme know what you think!


End file.
